Particles from many different sources are found in transformer oil. These are just a few examples. The file that follows contains images of
specific types of particles with reference to their source.
New Paper Fiber
Aged Paper Fiber
Other Aged Cellulose
All of the particles that follow are from one 50 milliliter oil sample collected from a 8400 kVA
Transformer. The transformer reportedly had a gas blanket and was sealed. The particles indicate
otherwise. The large number of degraded paper fibers in this sample indicate severe degradation of
the paper insulation and there is evidence of charring of the paper at some locations.